create-typescript-x402-nextjs

Use the proxy pattern by creating a middleware.ts file at the project root with paymentProxyFromConfig, defining route patterns with prices and your Algorand payTo address. Alternatively, wrap individual route handlers with the withX402 function for per-endpoint control.

paymentProxy centralizes route protection in middleware.ts and settles payment when forwarding the request. withX402 wraps individual route handlers and only settles payment when the handler returns a status below 400, protecting users from paying for failed requests.

Yes, specify the USDC ASA ID in the route config's extra.asset field, such as USDC_TESTNET_ASA_ID (10458941) for testnet or USDC_MAINNET_ASA_ID (31566704) for mainnet. The price field still uses dollar notation like "$5.00".

The middleware.ts file must be located at the project root next to the app directory, otherwise Next.js will not load it. Also verify the matcher config targets your API routes, such as "/api/:path*", and that PAY_TO is set in .env.local.

Yes, provide an array of accepts entries in the route config, one with ALGORAND_TESTNET_CAIP2 and one with ALGORAND_MAINNET_CAIP2, each with its own payTo address. Clients can then pay on either network.

With the proxy pattern, exclude free routes from the middleware matcher or omit them from the routes config. With withX402, simply do not wrap the handlers of routes that should remain free.